An emj captain reported that the lavatory smoke warning occurred just after pushback.

Attributes
ACN	589474
Time
Date	200308
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Embraer Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	ground : parked
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	589474
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	non adherence : published procedure other anomaly
Independent Detector	aircraft equipment other aircraft equipment : lav smoke alarm other flight crewa
Resolutory Action	aircraft : equipment problem dissipated
Consequence	other
Supplementary
Problem Areas	Maintenance Human Performance
Primary Problem	Maintenance Human Performance

Narrative:

Following engine #2 start the ramp personnel began to remove ground service equipment. An airstart cart and gpu were attached since the APU was inoperative. During the process a lavatory smoke warning occurred including the aural alarm. Complied with checklist. Flight attendant indicated there was a smell in the cabin just prior to the alarm. Flight attendant completed a check of the lavatory area and could not find a culprit for the alert. The ramp crew chief advised us over the intercom that the airstart cart may have been removed out of proper sequence. Fumes from the start cart may have entered the cabin area. Operations, maintenance, and company advised. Maintenance completed checks and signed off. Evacuate/evacuation was not performed. Passenger were deplaned to allow for maintenance check.

Original NASA ASRS Text

Title: AN EMJ CAPT RPTED THAT THE LAVATORY SMOKE WARNING OCCURRED JUST AFTER PUSHBACK.

Narrative: FOLLOWING ENG #2 START THE RAMP PERSONNEL BEGAN TO REMOVE GND SVC EQUIP. AN AIRSTART CART AND GPU WERE ATTACHED SINCE THE APU WAS INOP. DURING THE PROCESS A LAVATORY SMOKE WARNING OCCURRED INCLUDING THE AURAL ALARM. COMPLIED WITH CHKLIST. FLT ATTENDANT INDICATED THERE WAS A SMELL IN THE CABIN JUST PRIOR TO THE ALARM. FLT ATTENDANT COMPLETED A CHK OF THE LAVATORY AREA AND COULD NOT FIND A CULPRIT FOR THE ALERT. THE RAMP CREW CHIEF ADVISED US OVER THE INTERCOM THAT THE AIRSTART CART MAY HAVE BEEN REMOVED OUT OF PROPER SEQUENCE. FUMES FROM THE START CART MAY HAVE ENTERED THE CABIN AREA. OPS, MAINT, AND COMPANY ADVISED. MAINT COMPLETED CHKS AND SIGNED OFF. EVAC WAS NOT PERFORMED. PAX WERE DEPLANED TO ALLOW FOR MAINT CHK.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.